RESEARCH INDICATES LESS IS MORE

Mark Welterlen MWELTERLEN@PRIMEDIABUSINESS.COM

Water restrictions have been prevalent in many areas of the United States in recent years. While the arid West has always had to deal with drought, the East was severely affected in 2002. Water bans had a damaging effect on turf and landscape plants. What should you do if 2003 follows the same drought pattern? One approach is to develop a water conservation strategy before drought conditions hit. Irrigating deeper and less frequently is a recommendation that goes a long way to benefit turfgrasses like tall fescue.

Research at the University of California, Riverside, underlines the importance of deep, less-frequent irrigation in maintaining tall fescue under water deficit. In a two-year field study in Riverside, researchers evaluated the effects of water deficit (80 percent ETcrop/irrigation uniformity), water frequency (two, three or four irrigation events per week), cultivars (Shortstop, a dwarf tall fescue, and Jaguar III, a turf type) and mowing height (1.5 and 2.5 inches) on tall fescue visual quality.

During the first year, visual quality was significantly higher for Jaguar III and the lower mowing height. By the second year, when the turf was established, overall visual turfgrass quality was highest for plots irrigated at the lowest frequency — twice per week. Cultivars and mowing height were not important factors in the established turf. Visual quality also was highest with higher soil water content. Therefore, the results of this study advocate deeper, less frequent irrigation of established tall fescue under water deficit.